imporved error handling func hash helper

data/data.go

@@ -22,6 +22,7 @@
 package data
 
 import (
+	l "log"
 	"strconv"
 	"time"
 
@@ -183,8 +184,13 @@ func (n *Node) Convert() *meshv1.Node {
 // Convert a given mesh node to a database node
 // with a given state of the node
 func Convert(n *meshv1.Node, state int) *Node {
+	id, err := h.Hash(n.Target)
+	if err != nil {
+		l.Printf("Could not get the hash value of the ID, please check the hash function")
+	}
+
 	return &Node{
-		Id:            h.Hash(n.Target),
+		Id:            id,
 		Name:          n.Name,
 		Target:        n.Target,
 		State:         state,
@@ -195,11 +201,20 @@ func Convert(n *meshv1.Node, state int) *Node {
 // Get the id of a database node.
 // The id is a hash integer
 func GetId(n *Node) uint32 {
-	return h.Hash(n.Target)
+	id, err := h.Hash(n.Target)
+	if err != nil {
+		l.Printf("Could not get the hash value of the ID, please check the hash function")
+	}
+
+	return id
 }
 
 // Get the id of a given sample.
 // The id is a hash integer
 func GetSampleId(p *Sample) uint32 {
-	return h.Hash(p.From + p.To + strconv.FormatInt(p.Key, 10))
+	id, err := h.Hash(p.From + p.To + strconv.FormatInt(p.Key, 10))
+	if err != nil {
+		l.Printf("Could not get the hash value of the sample, please check the hash function")
+	}
+	return id
 }

data/data_test.go

@@ -70,6 +70,10 @@ func Test_NewMemDb(t *testing.T) {
 	}
 }
 
+// helper function
+func value(n uint32, _ error) uint32 {
+	return n
+}
 func Test_Convert(t *testing.T) {
 	tests := []struct {
 		name          string
@@ -88,7 +92,7 @@ func Test_Convert(t *testing.T) {
 			},
 			state: 1,
 			expectedNode: &Node{
-				Id:            h.Hash("tegraT"),
+				Id:            value(h.Hash("tegraT")),
 				Name:          "test",
 				State:         1,
 				Target:        "tegraT",
@@ -98,7 +102,7 @@ func Test_Convert(t *testing.T) {
 		{
 			name: "Node to MeshNode",
 			inputNode: &Node{
-				Id:            h.Hash("tegraT"),
+				Id:            value(h.Hash("tegraT")),
 				Name:          "test",
 				State:         12,
 				Target:        "tegraT",
@@ -142,12 +146,12 @@ func Test_GetId(t *testing.T) {
 		{
 			name:       "Node with target",
 			node:       &Node{Target: "tegraT"},
-			expectedId: h.Hash("tegraT"),
+			expectedId: value(h.Hash("tegraT")),
 		},
 		{
 			name:       "Node without target",
 			node:       &Node{},
-			expectedId: h.Hash(""),
+			expectedId: value(h.Hash("")),
 		},
 	}
 
@@ -174,12 +178,12 @@ func Test_GetSampleId(t *testing.T) {
 				To:   "Gose",
 				Key:  1,
 			},
-			expectedId: h.Hash("EagleGose1"),
+			expectedId: value(h.Hash("EagleGose1")),
 		},
 		{
 			name:       "Empty samples",
 			sample:     &Sample{},
-			expectedId: h.Hash("0"),
+			expectedId: value(h.Hash("0")),
 		},
 	}
 

helper/helper.go

@@ -103,10 +103,13 @@ func ValidateAddress(domain string) bool {
 	return RegExp.MatchString(domain)
 }
 
-func Hash(s string) uint32 {
+func Hash(s string) (uint32, error) {
 	h := fnv.New32a()
-	h.Write([]byte(s))
-	return h.Sum32()
+	_, err := h.Write([]byte(s))
+	if err != nil {
+		return 0, errors.New("Generating a hash value failed: " + err.Error())
+	}
+	return h.Sum32(), nil
 }
 
 // ------------------

mesh/mesh.go

@@ -382,13 +382,21 @@ func (m *Mesh) retryPushSample(node *meshv1.Node) {
 // Get the ID of a node
 // Hash integer value of the target field (name of node)
 func GetId(n *meshv1.Node) uint32 {
-	return h.Hash(n.Target)
+	id, err := h.Hash(n.Target)
+	if err != nil {
+		log.Printf("Could not get the hash value of the sample, please check the hash function")
+	}
+	return id
 }
 
 // Get the ID of a sample
 // Hash integer value of the concatenated From, To and Key field
 func GetSampleId(p *meshv1.Sample) uint32 {
-	return h.Hash(p.From + p.To + strconv.FormatInt(p.Key, 10))
+	id, err := h.Hash(p.From + p.To + strconv.FormatInt(p.Key, 10))
+	if err != nil {
+		log.Printf("Could not get the hash value of the sample, please check the hash function")
+	}
+	return id
 }
 
 // Setup the Logger